1. Field of the Invention
The invention relates to a module for integrated control electronics, that is, to a housing concept for integrated control electronics, comprising a housing base, an interconnection substrate populated with electronic components of the central control electronics and a signal and current distribution component as the electrical connection between the central control electronics and peripheral components, and to a method for manufacturing such a module, particularly for transmission or engine control systems in the automotive industry.
2. Prior Art
In automotive engineering, components such as transmission, engine or braking systems are increasingly mainly electronically controlled. The trend here is toward integrated mechatronic control systems, i.e. to the integration of control electronics and the associated electronic components such as sensors or valves into the transmission, the engine or the braking system. Control devices therefore generally have a large number of electronic components which are connected to other components outside the control device. In the case of “peripheral electronics” of this kind, these control systems are no longer accommodated in a separate protected electronics compartment and therefore have to withstand corresponding environmental effects as well as mechanical, thermal and chemical stresses.
For this purpose, they are normally installed in special housings which also perform an important shielding function. In order to provide a reliable connection to components outside the housing, an electrical connection from the inside to the outside of the housing is necessary.
The usual structure for such integrated mechatronic applications consists of a ceramic substrate containing the different electronic components of the central control unit. Said ceramic substrate is bonded to rigid or flexible circuit boards in order to enable the peripheral components to be connected to the central unit. As already described, transmission control modules, for example, are accommodated in the transmission oil sump and therefore completely surrounded by oil and the conducting contamination contained therein. This can be, for example, contaminations from gear tooth abrasion, machining residues from production processes or inadequate washing and cleaning of the transmission housing and/or the installed components. To provide the necessary protection against such contamination, damage and conductor track or bond shorts, a form of lidding, usually as a metallic, non-metallic or metalized housing cover, is placed onto the housing base plate and hermetically sealed. This composite structure comprising ceramic substrate, circuit boards and their links to the electronic connection of the peripherals as well as the hermetically sealed housing is a significant cost driver. In particular the LTCCs (low temperature cofired ceramics) preferably used as interconnection substrates which are mounted on a base plate to provide mechanical stability and thermal connection, constitute a major cost factor for the component as a whole. Their electronic connection via flexible circuit boards or leadframes to the components outside the sealed housing is also complex and therefore costly.